Radio-circuit-testing instrument



oci. 1s, 19u27. 1,646,152

J. o. KLEr-:R

RADIO CIRCUIT TESTING INSTRUMENT Filed May 20.. 1926 /5 Jgl Patented Oct. 18, 19277.

UNITED- STATES PATEN T1g *ePRICE Jackson QKLEBER, or PITTSBURGH, PniNsyLvnNIA;

nADIo-cIRcUIT-TESTING INSTRUMENT.

Application iled May 20,

the electrical connectionginay be quickly lo-V cated. -A .fur-ther object is to provide a testing apparatus which is .simple in construction and which, therefore, can be manufactured at relatively low cost. Additional features and' advantages of this inventionV will appearfrom the following' description considered in connection `with the accompanyving drawing forming part of this application and in which F ig. 1 is :a front elevation of the box-,por-

' tion ofl a testing apparatus designed for testing a well known make ci radio receiving instrument operating-,1 in the present example, with sixv electron-tubes, all standard parts ofithis receiving apparatus being shown in dot and dash lines. V 1 y Fig. 2 is the comb-like contact portion of the testingapparatus. f y Fig. 3 is a top plan view, partly broken away, of the box-portion. 'y

Fig. fi shows the relative position of the comb-like contact-portion when applied to f theradioreceiving apparatus, shown in dot and dashlines.. lFig. 5y shows the holding-clamp used for attaching ,the` contact-portion to the radio receiver.'y i l Fig. 6 is a cross-section through thezboxortion of the testing apparatus, taken on ine 66Figs. 1 and Fig. Z is afractional bottom view ofthe box-portion.

Fig. 8 is a diagraml showing some ofthe 1wiring connectionsin the box-portion. A Fig. 9 is a top-viewV ot the six-tube radioreceiver shown in Fig. 1. ...Reference being had to the drawing which shows the application of this invention to a six-tube radio-receiving instrument A of a well known make, it will be notedthatzthe -testi-ng apparatus comprises vtwo principal parts, namely the box-portionV B and the cenit-like eelitactfportontG.

192e. Aseriarim. 110,438.

The box-portion consists ofafrectangular box 1 having a cover 2 upon which are placed4 two parallel rows 3 and 4 of oppositelypdisposed contact points 5 and 6. The former are numberedconsecutively to indicate the numeral of the test ywhereas the other contact points are annotated to indicatetlie various voltages which should beobtained at keach Y test. ,Thesevoltages are read-on a voltmeter Y"I deriving 'its Lcurrent from an electrical battery 8,` both elements being. connecte-d by Vmeans of the terminal posts Qand the wiresV 10.- to theparallel metal slide-bars 11fand 12 which are placed on` the cover 1 andcarried by the' insulated supports 13.y These bars serve, as vguides forA a lcontact-slide '14A made ofv insulating;materialiiand havingV at its under-side `two separate contact blades: 15 and 16 adapted toengagerespectively-:thek v contact points in the rows 3 and 4.

t Mounted onjtheunderside of the box-member 1 is a strip 17 of insulating, material upon which are properly :located the gang-plugs f 18,`- (six` inthe presentr embodiment) having f the four contact-pins 19 offproper lsize and .disposition to it within theksockets20 in which the six electron-tubes of the receiving instrument arey normally mountedl f These contact pinsare properly, connected, (tosuit the wiring` diagram of the receiving instrument) by means of wires placedwithin .the box 1 to the inwardlyr protruding ends 21 of the contact-points .5 and `6.

Thecontact-portion fCfconsists `.of a strip of insulating material upon `which arer secured the substantially` L-shaped and resilient contact ingersx23, equal in number and spacing tovthat of the, terminals 2li forming part -ofgthe radioy receiving instrument` A.

These :various contact' iingersare also connected by means of wires 251` yot suitable length and the connectors 26 to the proper contact-points()` and 6. vFor ease Iof han- (lling, these numerous .wires are preferably bunchedftogetherto form a single cable indicated `by `thenumeral27 in various figures.r

`To establishy the required testing circuits, `the various contact-fingers k23 `must jbe brought simultaneously'l in` proper. engagement rwith their corresponding terminals 24.

To that eifect,;tliere are secured at `'both` rends `of the strip 22 thehangers l28fwlf1ichare suitably bent to rproducea bight 29 adapted to .tit abouttheter-Ininal strip 300i the receiving instrun'ient--v The, desiredcontact. pressure of the fingers 23 on the terminals 2a is obtained by means of screws 3l provided in the bridge-portion of the hangers.

In order to test a radio-receiving instrument by means ot this testing apparatus, the electron-tubes of said instrument are iirst removed and the gang-plugs of the box-portion are inserted in their stead; the comblike contact-member C is then mounted on the terminal-strip to press the contactlingers 23 on -the terminals Q11-, and the voltmeter 7 with'its battery 8 are now connected to they terminal posts 9. The various connections in the radio-receiving instrument e may Anow be tested by passing the contactslide successively over the various contactpoints in the two rows?, and 4. As 'stated before, the voltage to be expected for each circuit in the receiving instrument is indicated at the side of each contact point of row il. rIn order to inform the instrument rtester of the meaning ofthe various circuit numerals, a test-table 32 having the required information is placed on: one side of the boX- portion.k Thus for instance, when the contact-slideis on the first set of contact-points,

the connections to the rheostat of the radio- 'receiverr can be tested as to their voltage and condition. If no voltage is indicated on the voltmeter 7, it means that said connection isk brokenor loosened. Similarly if no voltage `is read on the voltmeter when the contact slide is on the second'set of contact points, it indicates that the battery switch contact Vis loose or defective and, Vthat,therefore, the trouble should be looked tor at this place, and so forth.

Tt will be appreciated that by means of thisftesting apparatus all connections of a receiving instrumentcan `be tested in only a small fraction of the time now required vfor doing this work by the old method which requires dismounting part of the receiving instrument 'and tracing each circuit wire for wire. Y Since the main object of testing a receiving apparatus is to ascertain whether o r not all the wire connections are perfect, the knowledge of the Vvoltage at each-connection is'not absolutely necessary and, therefore, the voltmeter may be replaced by a. `less fragile and cheaper device such as an electric bell or buzzer. The sounding of said device will then indicate that the tested connection is satisfactory and theV absence of sound will denote a broken connection.

The construction of the testing Vappara.-

I tus is, ofcourse, modified to suitl the type of receiving instrumentfand the-number of electron-tubes used therewith. Thus a four-tube receiving set would have four gang-plugs118l and the proper number of {contact-points 5, 6` and of contact-fingers 23.

This testing apparatus is especially intended for manufacturers, wholesalers and retailers, who must test each apparatus before it is sold to the public. ln view of the limited number' and sizes and types of standard receiving instruments handled by each distributor, the latter would only be required to provide himself with but a few testing apparatuses for testing purposes.

YVhile I have illustrated and described herein the preferred embodiment of my invention, and one which l have found by actual use vto be very practical, it may be thought desirable after continued experience to make slight changes in the construction and arrangement of the details oit my invention, and I intend to include in this application all such variations as fall within the scope of the appended claims. l

I claim: f

l. In a testing apparatus for radio-receiving instruments of the character described, a box portion having a plurality of gangplugs adapted to fit the sockets of the electron-tubes of said instrument; a contactstrip" having a. pluralityv of contact-fingers' adapted to engage simultaneously an equal number of terminals ofsaid instrument, a plurality of contact points positionedon said box portion; a' sliding contact-member adapted to slide over said contact-points 'and engage two thereof simultaneously; metallic slide bars for guiding said sliding contact member; electrical connections for connecting into definite circuits said; gang-plugs, contact-ingers and terminals to said contact points, and means for sending a test current through any circuit defined by a pairV of contact pointsengaged by said sliding-contact-member. l

Q *In a testing apparatus for radio-receiving instruments of the character dcscribed, a box portion having a plurality of gang-plugs adapted to lit the sockets or the electron-tubes of said instrument; a contactstrip having-a plurality of contact-fingers adapted to engage simultaneously an equal number of vterminals of said instrument, means tor fastening said contact-strip to the terminal-strip of said instrument, a plurality of contact points positioned onsaid box-portion; a sliding contact-member adapted to slide over said contact-points and engage two thereof simultaneously; metallic slide-bars for guiding said sliding contact-member; electrical connections for connecting into delinite circuit-s said Vgangpl-ugs, contact-lingers and terminals to'v said Contact. points, means for sending a test current through any circuit deiined by apair of contact-points engaged by said slidingcontact-'member and adjustable means for pressing said contact-fingers against said terminals.

8. In a testingapparatus'for radio-recev-- ing instruments of the character described; a box-portion having a plurality'of gangplugs adapted to fit the sockets of the electron-tubes oit the instrument to `be tested; a contact-strip having` a plurality of contactiingers adapted to engage simultaneously the terminals ot' said instrument; a plurality of contacbpoints positioned on said box-por tion; electric connections for connecting into delinite circuits said gang-plugs; Contact vngers and terminals to said contact-points;

a source of electrical energy; means cooperating with said contact-pontsfor closing any selected circuit, and means for sending a test-current from said source of electrical energy into said circuit. y

l. In a testing apparatus for radio receivng instruments of the character described, a box portion; a plurality ofgangplugs adapted to fit the sockets of the e1ec,

tron-tubes of the instrument to be tested; a plurality of 'contact-points positioned on said box-portion; electric connections for connecting into definite circuits said gangplugs and contact-points; a source of electrical energy; means cooperating with said contact-points for closing any selected circuit, and means for sending a test current from said source of electrical energy into said circuit. y

In testimony whereof I ax my signature.

JACKSON o. KLEBER. 

